Cam grinding machine



l Nov. 2, 194s.

H. w. BRowN GAI @BINDING MACHINE 6 Sheets-Sheet 1 Filed Dec. 18, 1943Nov. 2, 1948. i I H. w. BRowN 2,452,989

l cAu @BINDING MACHINE Filed Dec, 18, 1943 6 sheets-sheet 2 H. w. BROWNcm @alumna uAcHINE Nov'. z, 194s.

6 Sheds-Sheet 3 Filed Dec.' 1s. 1945 I I I I I I Nov. 2, 1948. Hjw.BRowN I CAM GRINDING MACHINE e sheets-sheet 4 Fnd nec. 1a. 194s Nov. 2,1948. H. w. BROWN l 2,452,989

cm GRINDING MACHINE Filed Dec. 1a, 1945 e sheets-sheet e Patented Nov.2, 1948 UNITED STATES PATENT ori-ICE f 2.45am i CAM GamnlNGvMAcnma HarryW. Brown, Cleveland, Ohio, asignor to The National Acme Company,Cleveland, Ohio, a corporation of Ohio l .application December is, 194s,serial No. 514,806

(Cl. 51-10l)4 13 Claims.

This invention relatesto machines for grinding internal and externalcams and `more particularly to what are known as accelerating` camgrinding machines, the principal object being the provision of a machinecapable of grinding multiple cam surfaces on either the inner or outerperipheral surface of a work piece such as a die cup for dies.

A further object of the present invention is the provision of a camgrinding machine provided with a reciprocal table having a very slightmovement of as little as 1%" with a very rapid back and forth motion.

A further object of the invention is the provision of means for rotatingthe work holding table to permit the grinding of tapered cam surfaces.

A still further object of the invention is the provision oi. areciprocating table adapted to move the grinding tool at right angles tothe reciproeating movement of the work holding table.

A still further object of the invention is the g provision of means forrotating the spindle of the work holding head in which provision is madefor changing the ratio of rotation of the work holding means relative tothe master cam in order to grind a variable number of cam surfaces.'

A still further object oi the invention is the provision of hydraulic orfluid means for operating many of the parts of the machine in propertimed relation.. i

A still further'obiect of the invention is the provision of such a'machine that will be simple in construction, emclent and highly accuratein use and, at the same time, comparatively inexpensive to manufacture.

In the drawings accompanying and forming a part of this specification,

Fig. 1 is a side elevation of this improved machine.

Fig. 2 is a view of one end of the machine taken at right angles toFig. 1. l

Fig. 3 is a view taken on line 3 3 of Fig. 7.

Fig. 4 is a view of the opposite end of the machine to that shown inFig. 2 and illustrates the gearing for rotating the work at variablespeeds.

Fig. 5 is a detail of the operating handle and its shock absorbingmeans.

Fig. 6 is adetail of the operating handle taken at right angles to Fig.5. e l

Fig. 'I is a llongitudinal section through the work carrying headsomewhat enlarged and showing the spindle connection with the drivingmeans and the manner in which the head may be rotated for grindingangular surfaces.

2 Fig. 8 is an enlarged detail view showing the master cam and itsassociated parts for oper- 4 tion and mode of operation thereof, Idesire to lli have it understood that the invention is not limited tothe details o! construction and arrangement of parts illustrated in theaccompanying drawings since the invention is capable oi' otherembodiments, and that the phraseology employed is for the purpose oidescription and not of limitation;

The present machine comprises in general a base or frame 2 of anysuitable size and shape housing the Variousmarts of thehydraulic orfluid operating mechanism. Upon this 'base is mounted a shiftable orreciprocal table having secured thereto in any suitable manner a workholding head t and supported on the frame 2 at one end thereof is arotatable tool holding member l5 suitably carried for reciprocalmovement transversely of the table i.

For a-better understanding of the machine, the operation and structureof the various parts will be described separately.

The driving and controlling means for the table 3 in the presentinstance is hydraulically controlled by means of a double-actinghydraulic pump A. This pump receives fluid from a reservoir 6 bymeans'of the suction line Y and is suitably driven from a 'motor 'lconnected tothe pump by a belt 8 and pulley wheel `9. y

This double pump is provided with a high pressure low volume line R.leading from the high f pressure side of the pump running through a tiowcontrol valve P to a four-way pilot valve B and then to either end of acylinder I0 attached to the under side of the table 3. The course oi.'the fluid at each end of the cylinder is indicated by arrows and it willthus be seen that the passage to either end of the cylinder i0 willcause the cylinder'housing il to be shifted either to the right or leftand with it the table 3 and work holding head ii will be reciprocated atany desirled stroke or speed controlled by the flow control va ve P.

A spring pressed lever i2 is provided at the front of the base of themachine and when this 3 lever is pressed in, (see Fig. 6) the machine isstarted and when it is pulled out the machine is stbDDed.\ When in itsengaged` position (inward) the lever I2 is adapted to be engaged byadjustable dogs or lugs 'I3 suitablyfastened to the `side of the slide 3and contact with these dogs i 3 will cause the lever I2 to be rockedsideways to the left and right. The opposite end of the lever I2 isconnected by means of linkage Il to a pilot valve E which is connectedthrough the line S to the low pressure high volume side of the pump Aand to the four-way'pilot valve B to control the direction of movementof the table 3 and head I. On certain classes of work, the stroke orreciprocating movement of the table has to be very short and thismachine permits this stroke to be as short as 135" and shock to thevalve which would ordinarily result from such a short stroke whenreciprocating at high speed is prevented by means of the spring E. l Thework holding head 4 carried by this reciprocatlng table 3 is providedwith a rotatable -spindle I5 having at one end 4thereof a chuck or 4. Toeliminate any backlash of the gears, in

view of the train of gears required, a spring tension brake 22 (seeFigs. l, 3 and 7) is provided on the end of the spindle and this brakeprevents any backlash or lost motion.

In the particular structure illustrated, the machine is designed togrind four cam surfaces on the inner periphery of a work piece and thegearing I3, I9, 29 and 2| ls so constructed and proportioned that* thespindle I5 will be rotated at the proper speed for the grinding of fourcam surfaces. However, should it be desired to grind a greater or lessernumber of cam surfaces, provision has been made to vary the speed ofrotation of the spindle 5 as may be deemed necessary.

Intermediate the gear train I9, a swinging arm 23 is provided and bymerely changing the position of this arm and substituting the propergear, the

' speed of the spindle I5 may be changed. The

ratio of speed of this spindle to the speed of the master camhereinafter to be described must Aat all times be relative.

Since the cams have to be ground in variousl shapes, length of grooves,taper or straight, an adjustable work holding head has been provided sothat this head may be set at any desired horizontal angle relative tothe grinding tool. For that reason, the bevel gear box 25 and bevel geardrive 29, 2i is built in such manner that the work vholding head d maybe rotated at any angle relative to the tool for `diiferent'classes ofwork without affecting the drive 'of the work spindle I5. It will benoted that the swinging or rotating of the housing 4 on the table 3 willcause the gear 2i to rotate around its meshing bevel gear of the train20.

Located at one end of the machine is the 'grinder unit 5 having arotatable spindle 25 car- A and may be directly connected thereto orconnected by means of a belt 29, as illustrated.

This grinder unit 5 ls mounted on across sliding table 29 adapted toreciprocate transversely of the table 3. A suitable manually operatedwheel 30 provided with a section 3| having graduations thereon is fixedto a shaft 32 which is in turn connected by means of gearing 33 to a may-be obtained by the proper selection lof' gearing.

Mounted on the opposite end of this cam shaft is the master cam 36 andthis cam engages a roller 31 of a roller holding latch or lever 33pivotally connected or fastened by means of a stud 39 to the frame ofthe machine in such manner that the pivot peint will always bear thesame fixed relation to the cam shaft 35.

The transverse slide or table 29 is provided with a verticallypositioned T-slot 90 for the reception of a block 4I contacting thelever 38 and this block may be moved up or down in such manner that itsposition, together with the movement of the pivoted lever 38 by the cam36, will limit or control the reciprocating stroke of the table 29.

The complete operation of the machine and the relationship of thevarious parts will now be described.

A work piece, as i 1, to be ground with four cam surfaces is inserted inthe chuck or holding means I6 and the tool carrier 5 is provided withthe necessary grinding tool and properly positioned by the manuallyoperative Wheel 30.

Thereupon the motor 21 is started to start the grinding tool rotating ata very high speed. The hydraulic mechanism is then started to causefluid to be supplied to reciprocate the work table 3 and the lever I2 ispressed into engagement to control operation of the pilot valve E tocontrol the direction of flow of the fluid so that the table will beshifted back and forth.'

During these operations, the motor F is started Ibv means of the handcontrolled valve D to effect rotation of the gear trains i3 et seq. andthereby the work spindle I5 and also the cam shaft 35 and cam 36. Thegearing illustrated is such that the cam 86 will be rotated at fourtimes the speed of the work spindle I5 so that the tool may grind thefour desired cam surfaces by reciprocating the transverse tool table orslide 29 four times to each rotation of the work and during the entireoperation of the machine, the` work table 3 is reciprocated back andforth at a very high rate of speed to insure an even grinding of the camsurfaces.

From the foregoing it will be understood that while I have described thereciprocation of the work table in one direction with the tool slidereciprocating transversely thereto, 'these movements may be reversed ifdesired or one table may have a'dual reciprocation while the other.remained in a fixed position.

It is to be understood that by describing in detall herein anyparticular form, structure or y it may be made, or all or the modes oiits use, I claim:

`1. A cam grinding machine having a reciprocating work carrier rotatableabout its longitudinal axis for varying the angle of the work, meanslfor rapidly reciprocating said carrier, a rotata-ble work spindlecarried by said carrier, means ior rotating said spindle, areciprocating tool carfrier reciprocal transversely of said workcarrier,

means for reciprocating it, a rotatable. spindle carried by said toolcarrier, means for rotating it, and means for adjusting the position ofsaid tool carrier transversely of said work carrier.

ll .f6 l said carriersv reciprocating at a speed ratio relative to thespeed oi rotation of the spindle of the other, said reciprocating meansincluding fluid valve operating means for controlling the 2. A camgrinding machine having a reciprocat- I lng work carrier rotatable aboutits longitudinal axis for varying the angle of the work, means forrapidly reciprocating said carrier, a rotatable work spindle carried bysaid carrier, means for rotating said spindle, a reciprocating toolcarrier reciprocal transversely of said work carrier, means forreciprocating it, said last means including a cam rotated by the workspindle rotating means, a rotatable'splndle carried by said toolcarrier, and means for rotating it.

3. A cam grinding machine having a reciprocating work carrier rotatableabout its longitudinal axis for varying the angle of the work, means forrapidly reciprocating said carrier, a rotatable work spindle carried bysaid carrier,

tool carrier reciprocal transversely of said work carrier, means forreciprocating it, said last means including a cam rotated by the workspindle rotating means, means for rotating said cam at a speed ratiorelative to the speed of rotation of said spindle, a rotatable spindlecarried by said tool carrier, and means for rotating it.

d. A cam grinding machine having a reciprocating work carrier rotatableabout its longitudinal axis for varying the angle of the work, means forrapidly reciprocating said carrier, a. rotatable work spindle carriedbysaid carrier, means for rotating said spindle, a reciprocating toolcarrier reciprocal transversely of said work carrier, means forreciprocating it, said last means including a cam rotated by the workspindle rotating means, means for rotating said cam at a speed ratiorelative to the speed of rotation of said spindle, means for varyingsaid speed ratio, a rotatable spindle carried by said tool carrier, andmeans or rotating it.

5. A cam grinding machine having apair of carriers each provided with arotatable spindle, one carrying a work piece having a cam to be lmeansfor rotating said spindle, a'reciprocating stroke ofthe high speedcarrier, and means `for preventing shock to said iluid valve operatingmeans.

7. A cam grinding machine having a pair of carriers each provided with arotatable spindle, one carrying a work piece having a cam to be groundand the other a cam grinding tool, and reciprocal transversely of eachother, means for reciprocating one carrier at high-seed, one of saidcarriers reciprocating at a, speed ratio relative to the speed ofrotation oi the spindle of the other, said reciprocating means includinguid valveoperating means for controlling the stroke of the high speedcarrier, means for preventing shock to said iluid valve operatingmeanaand means for changing the relation of said speed ratio.

8. A cam grinding machine having a reciprocating work carrier rotatableabout its longi` .tudinal axis for varying the angle of the work, iluidmeans for rapidly reciprocating said carrier, means for controlling thestroke oi.' said reciprocating carrier, means for preventing shock` tosaid iluid means, a rotatable spindle carried by said carrier, fluidmeans for rotating said spindle, means for changing the speed ofrotation of said spindle, a reciprocating tool carrier reciprocaltransversely of said work carrier, fluid means for reciprocating it,means for controlling the stroke of said last reciprocating carrier,means for controlling the speed of reciprocation thereof, means foradjusting theposition of said last carrier, a. rotatable spindle carriedby said last carrier, and means for rotating it.

9. The machine of claim 8 in which the means for reciprocating the toolunit includes a rotating cam.

- 10. The machine of claim 8 in which the means for reciprocating thetool unit includes a rotating cam so connected with the rotatable workspindle operating means that the work spindle and cam will rotate atdifferent relative speeds. 1l. A cam grindingmachine comprising areciprocating table, fluid controlled means ior reciprocating saidtable, iluid valve operated means for controlling the stroke of thetable., a work holder carried by the table, a rotary spindle carried bysaid work holder, means for rotating said spindle, a reciprocating toolunit, means for addusting it, cam means for reciprocating it and groundand the other a cam grinding tool, and

reciprocal transversely of each other, means for reciprocating onecarrier at high speed, said having connection with the means forrotating the work spindle and at predetermined speed ratio relativethereto, and means 'cooperating with said cam means for controlling thestroke of the reciprocating tool unit.

12. A cam grinding machine having a reciprocating work carrier, iluidmeans for rapidly reciprocating said carrier, a rotatable work spindlecarried by said carrier, iluid means for rotating said spindle, a,.reciprocating tool carrier reciprocal transversely of said workcarrier, iluid means for reciprocating it and including cam operatedmeans connected with the rotary work spindle operating. means, arotatable spindle carried by said tool carrier, means for operating it,and means cooperating with said cam operated means for controlling thestroke of the tool umts 13. A cam grinding machine comprising areciprocating table, uid controlled means for reciprocating said table,uid valve operated means e spindle and at a, predetermined speed ratiorel ative thereto.

l HARRY W. BROWN.

REFERENCES CITED The following references are of record in the -le ofthis patent:

UNITED STATES PATENTS Name Date Whitney Dec. 11, 1917 Number Number 8Name Date Van Norman -e Oct. 27, 1925 vTessky Oct. 30, 1928 Braren Aug.4, 1931 Scharf! Aug. 30, 1932 Olson Mar. 21, 1933 Olson f Nov. 7, 1933Sassen Aug. 4, 1936 Amidon Dec. 7, 1937 IMaglott Aug. 23, 1938 BickelJan. 10, 1939 Flanders Jan. 16, 1940 Aller et al.v Jan. 23, 1940'Rybicky July 1 1941 Mossdori' Dec. 23, 1941 Turrettini Mar. 10, 1942Herrmann May 26, 1942 4Atherholi: et al. June 15, 1943 Horton May 30,1944

